1. Field of the Invention
The invention relates to recovery, concentration and detection of heavy metal ions from dilute aqueous solution and to methods and compositions therefor and processes of preparing the composition. The invention is particularly concerned with the preparation and use of an ion exchange composition in which a material with ion exchange sites is linked to a substrate.
2. Description of the Prior Art
Heretofore recovery of metal ions has been effected from relatively concentrated aqueous solutions, usually acidic, containing at least 50 parts per million and more usually at least 1000 parts per million or 0.1%, using ion exchange materials such as ion exchange resins, e.g., in the form of beads or granules, or cellulosic material such as cotton fabric or with material having ion exchange sites deposited in or on a porous substrate such as cotton fabric, or silica gel or gamma alumina. However, none of these is as effective as would be desired for the concentration and recovery of heavy metal ions from dilute aqueous solution for the ready detection or recovery thereof.